How to read boot sector of USB keys

[DavidCooper]

Do NOT lie to me. I've tested for drive numbers 0x81,0x82,0x83,0x84,0x85 and none of them are the drive number of removable media. Why nobody help me at this forum? Gggghhhhrrr!

I did tell you it won't work on all machines, though it does work with QEMU's BIOS on all my machines, so I suspect it may work on any machine if you work through QEMU. If you can't get it to work there, there's most likely a bug in your code, though alternatively it may be that the whole thing's being messed up by DOS in some way, given that that's what you seem to be booting up the machine with in the first place, but that's outside my knowledge as I never use DOS as a bootloader (and I doubt that anyone else here does either).

[Geri]

most bios have hard disk emulation for usb pendrives for dos compatibility and boot ability, so if you actually boot from it, it will be just act like a generic hard disk accessed through 0x80.

[Combuster]

Do NOT lie to me.

I didn't see anything wrong in David's post. However:

Why nobody help me at this forum?

It is you who must not tell lies.

*Ahem*


Dear Hercules,

It's become painfully obvious you're not good enough for this. Not even close. Do yourself a favour and find a new hobby.

[nerdguy]

Hercules,
Can you tell what drive number you get from the BIOS? What is the value of DL when your boot sector
is loaded? Where are you testing this?